The invention relates to a method and apparatus for assembling individual slide fasteners from a continuous fastener chain having longitudinally spaced gaps and, more particularly, to a method and apparatus for mounting sliders on and fixing bottom stops to a continuous fastener chain and cutting the continuous fastener chain into individual slide fasteners.
It has been known in this industry to automate the assembly of slide fasteners to achieve increased efficiency and reduced manual labor. One such apparatus is disclosed in U.S. Pat. No. 3,629,926 wherein individual fasteners are produced from a continuous fastener chain. The apparatus of this patent requires a high number of individual mechanical steps, such that it is difficult to produce fasteners at very high speed. In this known apparatus, the sliders and bottom stops are carried by a swing arm into position along the feed path of the continuous fastener chain. First grippers grip the chain adjacent a leading end thereof and move the chain forward so that the leading end of the chain is threaded through the slider and top stop. With the slider positioned on the fastener chain, the top stop is deformed to clamp securely to the chain adjacent the leading end thereof and the swing arm returns to its original position. Second grippers then engage the leading end of the chain to advance the chain by a pre-determined amount such that the tail end gap comes in registration with a cutter. The first grippers return to their original position to hold the chain near the gap and the assembled slide fastener is cut at the gap from the continuous fastener chain. The second grippers then withdraw the individual slide fastener from the apparatus.
Another representative example of the prior art in this field is disclosed in U.S. Pat. No. 3,663,000 in which sliders are attached to a continuous fastener chain in the following manner. The continuous fastener chain is gapped at longitudinal intervals and fed to a slider assembler where the chain is stopped with the gap located at the assembly station. The gap is spread transversely enough to receive a slider. A slider attaching means receives a slider and approaches the chain gap from a lower position to set the slider in the gap. As the final step, the scoops of the chain stringer are threaded in the slider which has been stationarily set in the gap. According to this apparatus, the chain has to be temporarily held stationary while the slider is inserted in the gap, which takes a rather long time and makes it difficult to produce fasteners at relatively high speed.
Objects of the present invention include to provide a novel method and apparatus by which sliders can be mounted more efficiently at a high rate on a continuous fastener chain having longitudinally spaced gaps and to provide a novel method and apparatus for mounting sliders on and fixing bottom stops at a high rate to a continous slide fastener chain having longitudinally spaced gaps. Other objects, advantages, and novel features of the present invention will become apparent from the following description of the preferred embodiment and claims.